Circuit breaker



Dec. 17, 1935. v H. RAWLINS 2,024,744

CIRCUIT BREAKER Filed April 7, 1933 2 Sheets-Sheet WITNESSES: W

INVENTOR Herbal-z L. Raw/172s.

ATTORN Dec. 17, 1935. H, RAWUNS 2,024,744

CIRCUIT BREAKER Filed April 7, 1933 2 Sheets-Sheet 2 WITNESSES: INVENTOR I BY ATI'ORNE Patented Dec. 17, 1935 UNITED STATES PATENT OFFICE cmcurr BREAKER Pennsylvania Application April 7, 1933, Serial No. 664,911

. 10 Claims. (01. 200-127) My invention relates to circuit interrupters and particularly to circuit breaking devices which are ordinarily mounted in a more or less inaccessible place and are adapted to be operable by hook sticks or similar operating means.

The high voltage expulsion fuse is a device of this general type and probably possesses as severe operating requirements as any of the group. The fuse must be .securely'latched in the closed position in order to prevent the opening of the circuit due to the magnetic reaction accompanying heavy current overloads, and at the same time it must be readily removable for periodic inspection and renewal. Further, the fuse mechanism is frequently connected in an energized circuit at the time of its removal, this adding to the possibility of the operator coming in contact with dangermis voltages.

One object of my invention, therefore, is to provide means whereby an expulsion fuse or other circuit interrupting device can be removed from its supports, repaired or inspected, and replaced without the use of any tools other than a hook stick and without any possibility of injury to the operator.

Another object of my invention is to provide an improved means for pivotally supporting an expulsion fuse or other circuit interrupting device which is rotatable from the closed circuit to the open circuit position. My improved supporting means to permit the removal of the circuit interrupter when that device is in the open circuit position and to securely latch the interrupter in the closed circuit position.

Another object of my invention is to provide means whereby q expulsion fuses or other circuit interrupting devices which are mounted in inaccessible places may be readily serviced by an operator standing on the ground.

One form of expulsion fuse comprises a pair of insulators, each of which supports a contact jaw, a fuse mechanism for bridging the insulators and a means for pivotally supporting one end of the fuse mechanism adjacent one of the contact jaws, the fuse mechanism pivoting on its supported end to open and close the electrical circuit in much the same manner as the conventional disconnecting switch. A latch for holding the fuse in the closed position and an unlatching device whereby the latch may be released and the fuse moved to the open circuit position are ordinarily provided. This arrangement permits the removal of the fuse from the electrical circuit by a hook stick but does not permit the mechanical removal of the fuse from its pivotal support. In

- ing any tools other than a hook stick.

order to accomplish this mechanical removal it is necessary forv the operator to re-engage the fuse with some form of fuse removal equipment and this ordinarily means that the operator has to either climb the pole or otherwise bring him- 5 self in proximity to the fuse device.

My invention, however, possesses all of the desirable features of the previously known structures in permitting the moving of the fuse mechanism to the open circuit position through the 10 agency of a hook stick, and in addition, it makes possible the mechanical removal of the fuse mechanism and the replacement thereof in the fuse supporting means without the necessity of utiliz- 1 The features of my invention which I believe to be new are particularly pointed out in the appended claims, and for a fuller understanding of those principles, reference may be had to the accompanying drawings, in which:

Figure 1 is an elevational view of an expulsion fuse in the circuit closed position;

Fig. 2 is a fragmentary plan view of the latch utilized in this embodiment of my invention:

Fig. 3 is a fragmentary perspective view show- 2 ing the expulsion fuse of Fig. 1 in the open circuit position;

Fig. 4 is a fragmentary perspective view similar to Fig. 3 showing the method of disengaging the fuse mechanism from its support by means of a 30 hook stick; 7

Fig. 5 is a fragmentary perspective view showing details of the latch releasing and disengaging mechanism; and,

Fig. 6 is a fragmentary elevational view show- 35 ing'the hook stick and the disengaging means.

Referring to the drawings, the base I, which comprises a channel shaped piece of steel, has mounted thereon two insulators 3. Each of these insulators supports a contact jaw 5 which is 49 adapted to engage the fuse mechanism I when the device is in the circuit closed position. The lower insulator 3 (Fig. 1) also includes a means for pivotally supporting the lower end of the fuse mechanism; this will be described in some detail in a subsequent paragraph. Terminals 9 which are electrically connected to the contact jaws 5 are provided to permit-the connecting of the fuse in the controlled circuit. A latch H which consists of a piece of spring steel having 50 an opening therein l3 (Fig. 2) is rigidly affixed to the upper insulator 3 in order to retain the fuse mechanism 1 in the closed circuit position.

As shown in the drawings, the fuse mechanism 1 1 includes an outer tube It of glazed porcelain the projectin portion 53 of the hook stick 5| or other weatherproof insulating material, an upper cap ll of conducting material having surfaces IQ for engaging the upper contact jaw 5, a lower terminal cap 2| of conducting material having similar surfaces 23 for engaging the other contact jaw 5, and a pivoting and latching means which consists of four pins 25, 26, 21, and 28, projecting outwardly from a rectangular shaped member 29 forming a part of the lower terminal cap 2|.

An inner tube 30, of fiber or other insulating material is provided for enclosing the fusible element 32 which completes the electrical circuit between the two terminal caps. The lower terminal cap 2| and its associated member 23 have a passage (not shown) therethrough of substantially the same cross sectional area as the passage 34 within the tube 30 in order that the arc gases formed within the tube 30 incident to the interruption of the controlled circuit may be freely vented to the atmosphere.

The pivotal support means associated with the lower insulator 3 comprises a substantially U- shapedframe 3| of conducting material, having opposed slots 33 for engaging the pins 25 and 26 which form a part of the lower end 29 of the fuse mechanism 1. It will be noted that the slotted openings 33 have a constricted portion 35 of less width than the distance between the outer surfaces of the pivot pins 26 and the latching pins 25. Thus, as shown in Fig. 1, when the fuse mechanism has been rotated about the pins 26 to the circuit closed position, the latching pins 25 have been moved from the position shown in dotted lines in Figure 1 to the position shown in full in that figure. In this position, since the pins 25 can be moved through the restricted portion 35 of the slots 33 only by rotating the fuse mechanism about the pivot pins 26, the lower end of the fuse mechanism is securely latched into engagement with the U-shaped frame 3|, and the magnetically produced forces which accompany heavy overload conditions are prevented' from causing the fuse mechanism to move from the closed circuit position. This latching of the lower end of the fuse mechanism 1 into the slot 33 in the support means 3|, in combination with the latch II on the upper insulator (the hole l3 in the flexible latch member engaging a pin 31 projecting outwardly from the upper cap I! of the fuse mechanism) securely holds the fuse mechanism in the circuit closed position.

A bifurcated support member 39 extends outwardly from the upper cap I! of the fuse mechan sm 1 and provides a support for the latch releasing and fuse disengaging member 4| which is pivotally connected thereto through the agency A of the pivot pin 43. Two cotter pins 45 prevent the pivot pin 43 from disengaging the opposed open ngs in the support member. The member 4| includes a rea wardly ex ending projection 41 for re eas g the latch durin the circuit openin op ration. an eve o enin 49 for en aging dur n the circuit opening operation. and a yoke 55 and a slot 51 for engaging the hook stick 5| .dwin the disen a in operation. The hook of steel, and a projecting hook portion 53 which ext n s outward y from the cap.

To move the fuse mechanism from the closed circuit position (shown in Fig. 1) to the open circuit position, the projecting portion 53 of the hook stick 5| is inserted in, the eye 49 of the latch releasing member 4|. A downward pull onthe hook stick 5| causes that member to ro- 5 tate about its pivot pin 43, thereby lifting the latch out of engagement with the projection 31. A further downward pull on the hook stick will result in the rotation of the fuse mechanism 7 about its pivot pins 26, to the position shown in Fig. 3. In this position, the projecting pins 28 engage suitable recesses 59 formed in the upstanding sides of the U-shaped support 3| and thereby prevent further rotation of the fuse mechanism and, at the same time, serve to sup- 15 port the fuse mechanism. v

To remove the fuse mechanism entirely from the support frame 3|, it is necessary merely to remove the projecting portion 53 of the hook stick 5| from the eye 49 of the latch releasing 20 member 4|, to rotate the hook stick 180 degrees, insert the projecting portion 53 in the slot 51, and move the stick so that the yoke 55 engages the body portion of the end cap 56 on the hook stick.

It will be seen that the yoke 55 acts as a fulcrum 25 for the hookstick 5| and that the projecting portion 53 is thereby capable of supporting the entire weight of the fuse mechanism I. Then toremove the fuse mechanism, it is necessary merely to lift that mechanism upwardly ,and then move 30 it out of the U-shaped support frame 3|.

The opposed portions of the bifurcated support member are spaced aparta distance only slightly greater than the thickness of the flat portions of the member 4|. Thus, when the fuse mechanism 35 is supported upon the hook stick, relative sidewlse movement between the support member 4| and the fuse mechanism 1 is efiectively prevented. In the supported position, the weight of the fuse mechanism causes the lower surface I54 of the 40 member 4| to engage the surface I56 of the support member 39 (as is shown in Figure 6) and these surfaces definitely fix the angular relation of the fuse mechanism and the supporting hook stick. By virtue of these motion defining means, 45 relative movement between the fuse mechanism 1 and the hook stick 5| is entirely prevented dur ing the fuse removing operation, and in effect the lgluse mechanism is rigidly aflixed to the hook stic This simple method whereby the fuse mechanism may be removed from its support means is of particular value when servicing expulsion fuses or similar circuit interrupting devices which are mounted on the top of poles or upon sub-sta- 55 tion super-structure. Here the grave danger of coming into contact with one or more of the energized electrical circuits which may be positioned closely adjacent the fuse structure has made the manual removal of these devices an extremely hazardous undertaking. My invention, however, permits the entire operation to be carried out from the ground level and by the use of an insulated hook stick. Thus, there is no danger of the operator becoming injured, there is no necessity for climbing the pole or super-structure, and in addition, the entire operation may be com plelted in less time than has been heretofore possib e.

Toreplace the fuse mechanism after it has been inspected or repaired, it is merely necessary to re-engage the hook stick 5| with the yoke 55 and slot 51 exactly as described for the disengaging operation, to lift the fuse assembly I,

whichis then rigidly aflixed to the end of the 10 support means by the use of a hook stick without in any way endangering the safety oi! the operator. In addition, I have disclosed how this principle may be applied to a particular form of expulsion fuse in accordance with the patent stat- 15 utes. The principle, however, is capable of wide adaptation, and it is my intention thatthe language of the accompanying claims be accorded the broadest reasonable construction, and that my invention be limited only by what is explicitly 20 stated in the claims and by the prior art.

I claim as my invention:

1. In a device for opening and closing an electrical circuit, a pair of terminal members, a removable means for connecting said terminals, said 25 connecting means being adapted to pivot on one of said terminal members when moving from the closed to the open position, and means whereby said connecting means may be moved out of operative engagement with said terminals by a hook 30 stick, said meanscomprising a single member which is pivotally supported on one end of said connecting means and which is provided with means for establishing a ilulcrum for the body portion of said hook stick and means for support- 35 ing the weight of said connecting means on the hook portion of said hook stick.

2. In combination, a pair of stationary terminal members, a conducting means movable to open and to close the electrical circuit between -10 said terminals, means for pivotally supporting one end of said conducting means on one of said terminal members, and means whereby said conducting means can be disengaged from said supporting means by a hook stick which comprises 45 a body member having a length several times its greatest width and a means projecting outwardly from the axis of said body portion adjacent one end thereof, said disengaging means including a member pivotally supported on said conducting means and having a yoke portion for engaging the body portion of said hook stick and means defining a slot for engaging the projecting portion of said hook stick.

3. In combination, a pair of stationary terminal members, a conducting means movable to open and to close the electrical circuit between said terminal members, means for supporting one end of said conducting means on one of said terminal members, latching means for positively 69 latching said conducting means against movement when said conducting means is releasable in the closed circuit position, and means engageable by an operating stick for releasing said latching means, for moving said conducting means to the open circuit position, and for disengaging saidconducting means from. said supporting means.

4. In combination, a pair of stationary terminal members, a conducting means movable to open and to close the electrical circuit between said terminal members, means for pivotally supporting one end of said conducting means on one of said terminal members, releasable latching means for positively latching said conduct ng means against movement when said conducting means is in the closed circuit position, and means including a single element supported on said conducting means and engageable by a hook stick to effect the releasing 01 said latching means, the moving of said conducting means to the open circuitposition, and the disengaging of said conducting means from said supporting means.

5. In combination, a pair of stationary terminal members, a conducting means movable to open and to close the electrical circuit between said terminal members, means including a slot for pivotally supporting one end of said conducting means on one or said terminal members, releasable latching means for positively latching said conducting means against movement when said conducting means is in the closed circuit position, and means engageable by the projecting portion of a hook stick to release said latching means and to effect movement of said conducting means from the closed circuit position to the open circuit position, said latch releasing means including means for engaging the projecting portion and the body portion of a hook stick to efiect the removal of said conducting means from said support means by movement of said hook stick.

6. In combination, a pair of stationary terminal members, a circuit interrupting means responsive to abnormal electrical conditions in the connected circuit for bridging said terminals, means for pivotally supporting one end of said bridging means on one of said terminal members, said support means permitting the disengagement therefrom of said bridging means when said bridging means is in the open circuit position, releasable latching means for positively latching said bridging'means against movement when said bridging means is in the closed circuit position, and means engageable by the project-V. ing portion of a hook stick to release said latching means and to effect movement of said bridg- 40 ing means from the closed circuit to the open circuit position, said latch releasing means also including means for engaging the projecting portion and the body portion of a hook stick in order that said bridging means may be disengaged from said support means by said hook stick.

7. In combination, a pair of stationary terminal members, a conducting means movable to open and to close the electrical circuit between saidterminal members, means on one of said terminal members for pivotally supporting said conducting means, and means on one end of said conducting means for engaging said support means, said support means comprising a frame member having a slotted opening therein, said slotted opening having a constricted portion, said slot engaging means including a pivot pin for engaging said slotted opening to provide a pivot point for said conducting means, and at least one projecting member movable into said slotted opening only when said conducting means is being rotated on said'pivot pin, said projecting member serving to latch said conducting means when in the closed circuit position.

8. In combination, a pair of stationary terminal members, a ccnducting'means movable to open and to close the electrical circuit between said terminal members, means on one of said terminal members for pivotally supporting said conducting means, and means on one end of said conducting means for engaging said support means, said support means comprising a substantially U-shaped frame member, the closed portion of which is aflixed to said terminal member, the side portions of said frame having opposed slotted openings therein, said slotted openings having a flared outer portion, a constricted central portion, and an enlarged inner portion, said slot engaging means comprising a pivot pin for engaging the inner portion .of each of said slotted openings to provide a pivot point for said conducting means, and a projecting member movable into each of said slotted openingsonly when said conducting means is being rotated on said pivot pins,'said projecting members serving to latch said conducting means when in the closed circuit position and to prevent opening of the circuit by the'magnetic reactions accompanying heavy overload conditions. 3

9. In combination, a pair of stationary terminal members,a conductingmeans movable to open and to close the electrical circuit between said terminal members, means for supporting one end of said conducting means on one of said terminal members, and releasable latching means for positively latching said conducting means against movement when said conducting means is in the closed circuit position, said conducting means including a member supported thereon so as to be movable relative to said conducting means and stop means for defining the limits of said relative movement, said member, being engageable by an operating stick to effect the release of said latching means, the movement of said conducting means from one position to the other, and the disengaging and removal of said conducting means from engagement with said terminals, the release of said latching means being effected by moving said member relative to said conducting means. v 5f 10. In combination, a pair of stationaryterminal members, a removable conducting means for bridging said terminal members, means associated with one of said terminal members for pivotally supporting one end of said conducting means thereon in order that said conducting means may be swingable into and out of engagement with said other terminal member, and releasable latching means for positively latching said conducting means against movement'when 15 said conducting means is in the closed circuit position, said conducting means including a member pivotally supported thereon so as to be movable relative to said conducting means'and stop means for defining the limits of said relative 2 movement, said member being engageable by an operating stick to efi'ect the release of said latching means, the movement of said conducting means from oneposition to the other, and the disengaging and removal of said conducting 25 means from engagement with said terminals, the release of said latching means being efiected by, moving said member relative to said conducting means.

HERBERT L. RAWLINS. 

